Gov. Rick Scott signed into law Friday a controversial proposal authorizing school prayer.

Critics who had lobbied the governor to veto SB 98 immediately refocused their attention on school boards, warning that implementing the policy would guarantee a court battle.

The law, effective July 1, allows school districts to create policies that authorize students to deliver "inspirational messages" at public events.

Teachers and employees still cannot.

"Legislators are clearly inviting Florida school boards to plunge into a legal swamp," said Rev. Barry W. Lynn, executive director of Americans United for Separation of Church and State. "I hope school board members turn down the invitation. It's wrong to subject students to coercive prayer and proselytizing."

All along Scott has said that he supports prayer, so his decision to sign the bill wasn't surprising.

However, the governor's office said most of the calls and emails it received about the measure were in opposition.

Sen. Gary Siplin, an Orlando Democrat, sponsored the bill and has long argued that students should not be prohibited from praying during public school events.

He said Friday that he worked with the Senate's attorneys to ensure the measure would hold up in court.

"I'm very confident that it will withstand constitutional muster," he said.

The Legislature approved SB 98 largely along party lines, though several Democrats joined Siplin in supporting the proposal.

The "inspiration messages" will teach students tolerance and provide focus, Siplin said.

The American Civil Liberties Union, Anti-Defamation League and Americans United lobbied for a veto along with individual faith leaders who challenged the bill's constitutionality and said it could lead to bullying or intolerance.

"This was a bill that we said would alienate students, make them feel like outsiders in their own classrooms just because they don't belong to the same faith as some of their classmates, or possibly have them be compelled by peer pressure to participate in religious activity that differed from their own family's religious heritage," ACLU spokesman Baylor Johnson said.

David Barkey, the Anti-Defamation League's religious freedom counsel, said organizations are ready to sue but would hold off until a district actually decides to put the law into effect.

"I think that the organizations who are looking at this are going to wait until a school in fact adopts a policy under the law and how they implement it," Barkey said.

Friday was the deadline for Scott to sign the legislation, veto it or allow it to become law without his signature.

He signed the bill quietly and without fanfare.

Siplin broke the story via posts on his Twitter and Facebook pages.

He ended with his usual sign off for social media updates, "Praise God."